ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM
Hurricane Genevieve Discussion Number 12
NWS National Hurricane Center Miami FL EP122020
300 AM MDT Wed Aug 19 2020
Genevieve continues to have a well-defined eye embedded in a
central dense overcast with cloud tops temperatures to about -65C.
The various objective and subjective satellite intensity estimates
have trended down since the last advisory, and the initial
intensity is reduced to a possibly generous 100 kt. Infrared
imagery hints that the hurricane may be undergoing an eyewall
replacement cycle. However, there are no recent microwave data to
Genevieve continues to move a little more northward than previously
expected, with the initial motion now north-northwest or 335/9 kt.
Mid-level ridging to the north and northeast of the hurricane
should cause a turn toward the northwest during the next 12-24 h,
with this motion continuing through the balance of the forecast
period. The guidance has shifted a little to the east since the
last advisory, and the new NHC forecast track has been shifted to
the east of the previous track through 72 h. The new track keeps
the center offshore of the Baja California peninsula by 50-60 n mi.
The forecast track takes the center of Genevieve over steadily
decreasing sea surface temperatures, especially after 12 h. This
should cause rapid weakening to begin later today or tonight. The
new NHC intensity forecast shows little change in strength during
the first 12 h due to the chance the hurricane may undergoing an
eyewall replacement. After that time, the forecast follows the
rapid weakening trend of the previous forecast, with Genevieve
likely to become post-tropical by 96 h and a remnant low by 120 h.
The new forecast continues to lie above the intensity consensus.
The current forecast track requires a hurricane watch for portions
of the southern Baja California peninsula at this time. A
hurricane warning may be needed if succeeding forecast tracks
trend closer to the peninsula.
1. The center of Genevieve is forecast to move just west of the Baja
California peninsula. However, the forecast track is now close
enough to southern Baja California Sur that a Hurricane Watch has
been issued. Tropical storm conditions should spread across
southern Baja California Sur beginning this afternoon and
continuing through Thursday,
2. Large swells generated by Genevieve are affecting portions of the
coast of southern Mexico and will spread northward along the coast
of Mexico to the Baja California peninsula through Thursday.
FORECAST POSITIONS AND MAX WINDS
INIT 19/0900Z 20.2N 109.4W 100 KT 115 MPH
12H 19/1800Z 21.1N 109.9W 100 KT 115 MPH
24H 20/0600Z 22.1N 110.7W 90 KT 105 MPH
36H 20/1800Z 22.9N 111.6W 85 KT 100 MPH
48H 21/0600Z 23.7N 112.7W 75 KT 85 MPH
60H 21/1800Z 24.7N 114.2W 65 KT 75 MPH
72H 22/0600Z 25.8N 116.1W 55 KT 65 MPH
96H 23/0600Z 28.0N 119.5W 35 KT 40 MPH...POST-TROPICAL
120H 24/0600Z 30.0N 122.0W 20 KT 25 MPH...POST-TROP/REMNT LOW